1. Field of the Invention
The present invention relates to coupling devices and more particularly, to a quick-release coupling for refrigerant cycle system, which prevents refrigerant leak.
2. Description of the Related Art
When removing a mating male connector from a quick-release coupling of a refrigerant cycle system, a pressure-discharge process is simultaneously performed. Thus, a residual gas will be ejected out of the mating male connector and the quick-release coupling upon removal of the mating connector from the quick-release coupling. A quick-release coupling for use in a refrigerant cycle system is adapted for the extraction of refrigerant. According to conventional designs, when connecting the mating male connector to the quick-release coupling, the passage between the quick-release coupling/mating male connector and the refrigerant cycle system is blocked. When the user pushes the pusher pin of the quick-release coupling, the sealer of the mating male connector is opened, allowing fluid communication between the mating male connector, the quick-release coupling and the refrigerant cycle system. The passage is opened when the pusher pin of the quick-release coupling is operated to move the sealer of the mating male connector. After a refrigerant filling/cycling operation, the pusher pin is moved back, and the passage of the quick-release coupling and the passage of the mating male connector are blocked. At this time, the quick-release coupling and the mating male connector still have residual refrigerant left therein. The residual refrigerant will leak out of the quick-release coupling and the mating male connector after removal of the mating male connector from the quick-release coupling, causing environmental pollution and making harm to the user's health.